Teledyne 7600 - Infrared gas analyzer - operating manual - Manual (Page 72)

Operation Model 7600
Teledyne Analytical Instruments 72
the numerical value which upon reaching will
trigger the peak alarm.
Hysteresis: To prevent possible chattering when the
measuring value may exceed the set peak
concentration by only 1 time, the peak count has
an allowance in the hysteresis width.
Setting range:
Alarm value: 10 to 1000 ppm, 5 ppm step (initial value: 500
ppm)
Alarm count: 1 to 99 times (initial value: 5 times)
Hysteresis: 0 to 20 % of full scale (initial value: 0% of full
scale).
Action of peak alarm:
If CO concentration exceeds the alarm value, counting will begin.
If the number of peaks is over the set times per hour, the peak alarm
contact closes (ON). If it is less than the set times per hour, it is open
(OFF).
Figure 3-9: Peak Alarm Example
Figure 3-9 depicts the behavior of the Peak alarm where the alarm
count has been set to 5. At the point labeled (1), the peak count alarm is
turned ON since the alarm count has reached the threshold of 5 per hour.
Since peaks of more than 5 times within an hour occur between the